1. The Field of the Invention
The present invention relates to an elastic tire, such as a pneumatic tire, provided with means permitting measurement of the grip of a vehicle equipped therewith on a surface on which the tire rolls (rolling ground), such as a roadway. It concerns more particularly the determination of grip characteristics of such an elastic tire on rolling, based on obtaining physical parameters in the contact area between this elastic tire and the rolling surface.
2. The Related Art
It has already been proposed to carry out continuous measurements in the tread of a pneumatic tire while a vehicle equipped therewith is driving, in order to know in real time the forces which develop between a pneumatic tire and the ground. The patent document DE-A-3937966 may be consulted on this subject. Nevertheless, however interesting it may be, such information is still insufficient, since the driver, or even an automatic device such as those referred to by the well-known designations in the automotive field of “ABS” or “ESP”, is still incapable of anticipating a deterioration in the grip. One therefore contents oneself with noting a posteriori the exceeding of a grip limit, and as rapid action as possible is taken to control the vehicle.
There exists in this respect a need to obtain indications “in real time” of the grip conditions liable to affect, in the instants which follow, the behavior of a vehicle, notably in cases where it undergoes a substantial acceleration, due to driving or braking forces or to a change in trajectory.